Proximate and Microbial Profile of Couscous Yoghurt Produced from Soya Milk

This study investigated the effect of milk type and mixture ratio on the proximate composition and microbial profile counts of couscous yoghurt. Yoghurts were first made from cow milk (CM), soya milk (SM) and equal mixture of both types of milk at ratio 50:50. Couscous was then mixed with yoghurts from cow milk (CMCY); soya milk (SMCY) and cow-soya milk (CSCY) at ratios of 90:10, 80:20 and 70:30 (yoghurt: couscous), w/w for the three respectively. The experiment was designed based on 2 factors (milk type and mixing ratio) at 3 levels, each resulting in a total of 9 treatments. Cow milk yoghurt without couscous was used as the control. Proximate compositions were determined using standard methods. Total viable microbial counts of samples were also determined. There were significant differences (p<0.05) in the proximate composition and CSCY at ratio 70:30 had the highest crude protein. In addition, CMCY at ratio 90:10 recorded the highest mean value for fat, while SMCY at ratio 80:20 and 70:30 recorded the least mean value for fat. All the couscous yoghurt samples had total viable cell counts of (<9 log CFU) that are within the acceptable range according to Codex Standards. In conclusion, the study has shown that CSCY at 70:30 had the highest nutrient content. Moreover, the products were also found to have low levels of microbial profile.